Fig. 5

ALV-J inhibited the proliferation, maturity, and Ig gene CSR of B cell progenitors in vitro. a CCK-8 test for the mitogen responsiveness of CD117⁺ B cells. Test results showed that B cell proliferation was inhibited by ALV-J. **p < 0.01, two-way ANOVA was performed. b Three days after LPS stimulation, there were fewer cell clones in infected groups than in the control group. Moreover, cells in the infected groups were dispersed in the bottom of dish (magnification: ×100). c Changes in antibody-producing cells (IgM⁺ and IgG⁺ cells) by flow cytometry analysis. There were fewer IgM⁺ and IgG⁺ cells in the infected groups than in control uninfected groups. d and e Quantitation of c; **p < 0.01, ***p < 0.001, two-way ANOVA was performed to determine the statistical difference. f Changes in Ig gene CSR (from IgM to IgG) by flow cytometry analysis. CD117⁺ B cells were cultured with LPS + IL-4 for 4 d, followed by immunofluorescence intracellular staining for Ig genes. g, h Quantitation of f. Fold changes in (i) IgG and (j) IgM produced by CD117⁺ B cells activated with LPS + IL-4 after 4 d. **p < 0.01, unpaired t-test was performed to determine the statistical difference